Speaker
Description
This talk considers exotic hadrons containing two heavy quarks (or a heavy quark and a heavy antiquark). It is argued on very general model-indpendent grounds that in the heavy quark limit such exotic hadrons must exist as parametrically narrow states. Moreover, it is shown that there in this limit there will be multiple exotic resonances with the same quantum numbers and that some of these must be parametrically close to the threshold for dissociation into two hadrons each of which containing a heavy quark. While, it the charm quark is too light for the analysis to apply directly in the charm-anticharm sector, the talk will end with a discussion of whether this kind of analysis might give some insight into states which have been been identified as putative charm-anticharm exotics.
